It is generally known that the bullets from rifles and pistols often developed eccentric rotation (or wobble) after leaving the muzzle of the firearm. This phenomenon is generally attributed to the instability of the muzzle itself and/or the action of the exhaust gases on the projectile. It is also generally known that rifles and pistols in the higher calibers produce a substantial recoil on the firearm as a resultant force of the combination velocity/mass relationship of the projectile and propellent. The net result of this interaction destabilizes the muzzle considerably. Much effort has been placed on devices (known as Muzzle Brakes) to diminish this effect, with great success. These devices generally reduce the recoil via a resultant force obtained by the side or rear redirection of the exhaust gases.
This redirection of the gases also redirects the muzzle blast noise toward the shooter, greatly increasing the shooters perception of the blast noise. Some of this noise perception has been reduced by using smaller gas orifices which provide better gas diffusion. However, this is generally at the expense of an increase in recoil over that obtained with a muzzle brake with larger orifices.
A desirable objective is to increase the accuracy of a firearm by directing and controlling various portions of the exhaust gases in a manner as to achieve a balance between projectile stability, recoil, muzzle stability and perceived noise.